View Full Version : Which type of tumbler is better for Al?


viper6383
04-10-2007, 07:16 PM
We are really trying to answer this question for our small production Al parts. We need to bring them off the VMC and hopefully run through a couple stages of tumbling to acheive a nice polish or near polish. Are the cam type box shakers better or faster or are the bowl types better? I think the bowls are quieter but what about the job they do?

Brandon

Crash
06-18-2007, 01:49 PM
I like the bowl type better. We use rotating barrels and a vibratory bowl type. For a nice polished surface on aluminum, you will need to rough and finish tumble it. We use a plastic type of media for the rough tumbling. It leaves a soft, matte surface. It's a good surface to anodize. For a bright polished finish, ball burnishing is the best. We send a number of parts out for this process. There are some hard, ceramic media types that will put a nice finish on aluminum, but not as good as ball burnishing does. It approaches a hand buffed finish.

Good luck

viper6383
06-20-2007, 09:47 PM
When you say ball burnishing, what type of ball are you talking about? The stainless balls? what size? Can walnut shell do it but take longer? I know the ball media is expensive so I would need to be sure of my purchase for sure. Thanks for the reply.

Kevin Taylor
06-20-2007, 11:38 PM
Tub type I use work's great Noise is an issue but if it dosen't make noise it isn't going to doo anything for you plastic media leaves a good finish but if you have rough cut's ceramic first then fowellowed with plastic might be more to your licking Good Luck Kevin

Crash
06-21-2007, 09:14 AM
Ball burnishing media is a small very hard, steel media. It lasts almost forever, but is very heavy. That's why we send our products out for this process. You would need a heavy duty machine for ball burnishing. You would also need to have a machine with a continuous flow of fresh soap and water to keep the parts clean. I think a vibratory bowl type would be best for this.

http://www.vibratoryfinishing.com/media.htm

KOS
06-21-2007, 09:31 AM
for my anodizing I use a vibratory tumbler with the 1/4" plastic triangles to remove machine marks (i use the green ones), it will leave a matte finish. From here I then run it in walnut shells with rouge for about 36 hours. It brings the part to a very high shine. Since I want my anodized parts to look almost translucent I need to have a high polish before they go into the tanks...

Stepper Monkey
06-30-2007, 09:49 AM
The plastic media is good, but for ball burnishing to a mirror polish shine I use ceramic balls. They have to be run wet (water with a couple drops of a special soaplike solution) to keep the black crap from clogging up thier microsurfaces but they work like nothing else.
I like the bowl systems for the pyramid plastic and the ceramic cutting media, as it is much fatser than tumbling. However, the ceramic balls are the opposite. I run three bowls in a row with descending order of cutting grits, followed by a rotary tumbler with the ceramic balls for a final mirror shine.

Only two caveats; The balls need to be broken in first - easy to do, just run them with some scrap for an afternoon. Second, the surface needs to be pretty smooth before the balls will shine them up - the balls don't actually remove much material, they just remove the matte finish, so make sure they are well vibro'ed down to a fine grit cutting media first.

KOS
07-01-2007, 09:54 AM
hey stepper do the ceramic ball get in small areas? how big are they? The reason I go with the walnut shells is that they get in every nook and cranny.

thanks!

Stepper Monkey
07-02-2007, 10:55 AM
The balls are 2mm for the smallest, so nearly everywhere anyway. They do like to get in every little slot and invariably on every piece a few want to stay wedged in a narrow slit or hole, so a dental pick to knock them out is always by the tumbler! Don't know if wlnut shell does the same.

mxtras
07-02-2007, 12:02 PM
Can we get some folks to post some pics of the before/after, please? .

Include info on what media and what type of equipment and maybe some pics of the equipment and media, too.

Thanks!

Scott

KOS
07-03-2007, 07:20 AM
they can get stuck in some very tight spots, just depending on how tight the area is...usually they dont get stuck at all...here is a sample shot no the best pick but you will get a good idea of what it can do.

please note that the middle pic says bead blasting although this one was put through the tumbler with the 1/4" green pyramids...

KOS
07-03-2007, 07:21 AM
Hey Scott
Sorry I will have to take some pics of my set up and media for you, I only have an old shot of that part to post for now.... that is done with the set up i mentioned before...

mxtras
07-03-2007, 09:09 AM
I would like to see the set up. Thanks for posting the pic.

Is there a way to get into this kind of set up on the cheap? Did you build or buy?

Scott

KOS
07-03-2007, 09:34 AM
well I think it is a fairly reasonable price to get one set up... here is a link to the tumbler I have
http://www.eastwoodco.com/jump.jsp?itemID=10971&itemType=PRODUCT
here is the media I use, 1/4" green pyramids and walnut shell WITH rouge..
http://www.shorinternational.com/TumblingMedia.htm

I think most vibratory tumblers will work it will just depend on the size that you need for your parts....harbor frieght also sells an inexpensive one too, but I would reccomend getting the largest your budget can afford as you will enjoy throwing anything in there to get it cleaned up. Recently I took off the heat shields on my spark plugs for my car and polished them up too...

mxtras
07-03-2007, 10:21 AM
I am interested for the same reason this thread was started - to debur smallish parts from a milling operation. More interest for deburring than for polishing or surface finish.

Would you suggest the vibrating bowl or a tumbler for deburing operations?

Scott

KOS
07-03-2007, 10:30 AM
well some people say small parts and mean much larger stuff than what I make...so I just wanted to make sure...

I have both a rotary tumbler and a vibratory one. I dont like the rotarty one for multiple parts as the parts tend to bang into each other causing marks. The vibratory one just slowly moves them around in a circle. Although I will run both at the same time if I need the extra space, or sometimes on the rotatry if I am too lazy to change out the media and clean it out.

My personal preference is the vibratory over all...that may be though that I have just been more successful using it compared to the rotary. You can pick up are real cheap rotary one from Harbor frieght and test it out as well. I plan on adding a larger tumbler as well in the near future and it will be a vibratory as well.

For deburring parts they will work like a dream and you could get away with either of them, when I have used the vibratory for deburing it only needs to sit in there for a coulple of hours...not like the polish I showed in the pics that is a much more lengthy process to get done...

So since I have good success with my vibratory as you can see from my pics my reccomendation is the vibratory one..

mxtras
07-09-2007, 12:57 PM
well some people say small parts and mean much larger stuff than what I make...so I just wanted to make sure...

The parts I am discussing are made from 6061 aluminum and are:

1/2" wide by 1" long, 1/4" thick
3/4" wide by 4" long, 1/4" thick
2" wide by 4" long, 1/4" thick

I am looking to deburr and produce a somewhat uniform finish. They do not have any burrs - just sharp edges.

I have a few hundred of the smaller parts and am working to make a few hundred of the larger parts, too. At this time, I am pulling them from the machine, knocking the holding taps off on a belt sander and stock-piling the parts in hopes that I will either obtain a vibratory finisher (and all of the required knowledge) or hook up with someone that has the capacity that is close to me to save shipping costs. At this point, I will pay - at least until I get a set-up of my own. I will likely end up taking them to a local machine shop that used to make these parts for me.

Keep the info and the pics coming, please!

Scott

KOS
07-10-2007, 07:30 AM
with that type of volume you will def need to look at that largest bowl possible your wallet can afford. Otherwise you will only be doing a handful at a time.

The other option is to build one yourself. I think if you look on the net you can find some plans, I remember coming across some plans before but decided to just purchase my set up.

Basically you just put a motor underneath the bowl, and attach an offset weight to the shaft of the motor. So when it spins it makes the motor wobble and with the bowl sitting on some springs you will acheive a vibration.

Or simply build a couple decent size ones and you should be able to knock off those burrs.

I would say I could help you out but it doesnt look like I am close enough to you based on your post above.

BTW those MX holders are pretty trick!

Crash
07-10-2007, 10:03 AM
Some things to keep in mind about larger operations of this type ... You will be producing a waste stream, which will have to be dealt with somehow. It can't be dumped in the sewer system untreated. We have a large vibratory bowl plus two large banks of rotary barrel tumblers. All the waste water/metal sludge goes into an underground 1500 gallon 3 stage clarifier (replaced last year at a cost of 30K), then the outflow goes into the sanitary sewer system. I'm required to submit self monitoring reports twice yearly to the regulating agency. They can and do come out anytime they like to inspect and pull samples for their own lab. We have to watch the amount of chrome and nickel we get, because we tumble and deburr lots of 17-4 and other alloys. The tank has to be pumped every 2 years, at a cost of 6-10k. It's a hazardous waste. You might get away with doing it on a small scale for awhile, but even one small one will produce some amount of waste. Another consideration- the larger machine you get, the louder it is. Ours is about 6' across, maybe 3 or 4 cf capacity. It's uncomfortable to be in the same room with it. We have it out with the punch presses, in a separate room away from the main shop. If you are just polishing aluminum, and not removing much material, your waste problems will not be as bad.

Good luck

KOS
07-10-2007, 02:16 PM
I have always wanted to try out a wet system, however I have only ever tried the dry ones. I have read the wet lasts longer than dry does. Not sure on the difference of finishes though

EdgeCrusher
08-02-2007, 09:56 PM
We have bowl, barrel, and disk tumblers. All have their advantages and disadvantages. The Rosler disk high energy can do a machine line cut down in about 15 min and get a very high shine after cut down with paste and ceramic media in about a hour, but they are very expensive, high maintenance, and need a large footprint on the floor but work great for high volume. Bowl's are cheap and small and for a hobbiest or minimal use a great option. We have never had good luck with them the motors seem to burn up too fast, we have high production so they were running 6 day a week and we could only get about 2-3 weeks life out of the most of them so they didn't work for us. Honestly I still like the barrel or cam box shaker tumbler the best. We have had it for 10 years never had to do any maintenance not really that expensive. Only prob is like I've read on some of the other post is really loud and annoying and a little slow but if you can handle the noise thats my recommendation. Here's a couple links to the brands we use.
Rosler http://typo3.rosler.com/english/vibratory-finishing/high-energy-disc-systems.html

Roto-Finish the svp models are the barrel
http://www.hammondmach.com/content/view/289/195/

mxtras
08-03-2007, 09:22 AM
Nice looking equipment, EdgeCrusher.

Scott

EdgeCrusher
08-03-2007, 05:39 PM
thanks

smittys800
09-02-2007, 12:12 AM
I am also looking for that secret media to polish my parts to a nice mirror, or close to, finish. I just started to use the GREEN triangle plastic, WET. THat does a very nice job of a pre-polish, but takes my Corn Cob, mixed with Brasso FOREVER to bring the shine back.
What are your thoughts on Porcelin balls with Raytechs Compound "D"
Thanks,
Smitty

EdgeCrusher
09-06-2007, 09:04 PM
Hey Smitty I think we're all lookin for that secret media lol. Not sure of what kind of setup your using but I've used porcelin balls with a liquid compound not sure what it was at the time and I'm not really sure what the Raytechs Compound "D" is but it did an ok job but from my experience over the years I've found that after cut down media going to ceramic media with a light abrasive paste combination then to corn cob/treated walnut shells to work best to get a high shine finish. Unfortunatly I've yet to be able to replace hand buffing or Electro polishing for the mirror finish. Good luck.

smittys800
09-06-2007, 10:13 PM
Thanks Edge,
So far, my setup is 30min in the plastic media, 1 hour if I want ALL marks gone, then 4-8 hours in the Corn Cob. I just got some cob media from another Company, and does it do a nice job. Secret mix I am told. I will post the name of the company as soon as I find my paper work. Sure beats Brasso since they changed their Formula.
Smitty

xiphmont
10-18-2007, 02:43 AM
I am also looking for that secret media to polish my parts to a nice mirror, or close to, finish. I just started to use the GREEN triangle plastic, WET. THat does a very nice job of a pre-polish, but takes my Corn Cob, mixed with Brasso FOREVER to bring the shine back.
What are your thoughts on Porcelin balls with Raytechs Compound "D"
Thanks,
Smitty

Brasso is an unlucky choice! It contains (I believe) feldspar grit, and a rather coarse grit at that. I found out the hard way after running out of TurboBrite and grabbing a leftover bottle of Brasso in a pinch, and ruining a perfect mirror finish I'd just spent five days tumbling... it scratched the living heck out of the part.

My own experience:

I concur with everyone here about the green triangles. Best initial cut-down media I've found. I run them in a modified MT-14SV that has an added flow-through system.

My final polish is corn cob + activator (like TurboBrite) followed by untreated corn cob.

I tried porcelain ball (mix of 1mm/2mm/6mm) shot in the vibratory tumber and found it to be utterly useless, at least in comparison to just using corn cob or walnut shell. The corn cob worked faster and produced a better final shine. Perhaps shot is only useful in rotary tumblers?

I previously wrote this up all up in a project log... there are lots of pics of direct results using different media on identical parts behind the links:

http://xiphmont.livejournal.com/14116.html#cutid1 : Direct comparison of different media (pics of results from each)

http://xiphmont.livejournal.com/2007/10/16/ : Final results of green triangles followed by corncob/turbobrite followed by untreated corncob

Monty

BeerFizz
11-12-2007, 07:02 AM
well I think it is a fairly reasonable price to get one set up... here is a link to the tumbler I have
http://www.eastwoodco.com/jump.jsp?itemID=10971&itemType=PRODUCT
here is the media I use, 1/4" green pyramids and walnut shell WITH rouge..
http://www.shorinternational.com/TumblingMedia.htm


http://www.harborfreight.com/cpi/ctaf/Displayitem.taf?itemnumber=93832

Harbor Freight sells these "Green Triangles" for a pretty good price. Are these the same as those above? Has anyone used the Harbor Freight triangles?

Thanks

smittys800
11-12-2007, 09:41 AM
I have about 15 pounds of that and found it to be to aggressive for me. I called Mass Finishing... http://www.massfin.com/freesample.php
for some sample product, looks like 3/8" cone plastic material. About an hour in that, then over night in the Cob and I have chrome parts!!
I finally scored big, as I just got a MR. Deburr 3.0 cf machine from a machine tool auction, so now my little tumblers will do all the polishing and the big boy and do the hard work.
Smitty

Sinistersam
01-02-2008, 08:42 PM
Thank you for the write-up, xiphmont. Much appreciated, very helpful!